I'd have to disagree about the voice input. Voice might be fine for giving commands ("turn down the lights to 20%"), but I can't imagine trying to edit using voice. The moment you make a mistake or want to go back and change something, it gets ugly. Even getting the punctuation and paragraph layout would be miserable. There's a reason why, when manager-types dictate notes, someone has to then go and type it up to make it look pretty

I ran a full diagnostic on the oxygenator. Twice. It’s perfect. If anything goes wrong with it, there is a short-term spare I can use.

Not that he knows it at the time, but once Mark decides to start his farm, that would also be a backup source of oxygen, yes? (I'm not sure how much oxygen that number of plants would put out - might not be enough to make any difference)

They’re the most rugged and easily grown plants on earth, so I picked them to bring along.

Wouldn't NASA have dictated the exact nature of these experiments?

The total floor-space <of> the Hab is about 92 square meters.missing an "of"

Side note - When I was writing that section, I did the math on the Oxygen production of the farm. It's pretty low compared to a human's needs. I don't remember what it was but I remember it's nowhere near enough to support a person.

I read a short story when I was young called "Command", by Bernard I. Kahn (first published in 1947, but I read it in the 70s). In brief, it's about a spaceship that gets its oxygen from chlorophyll banks. A crewmember spits in the banks one night, contaminating them and rendering them all but useless. The crew then discovers that they don't have any spare media to recharge/regrow the banks (the same guy who spit in the banks traded the spares away to curry favor with someone). At the end of the story, the ship shows up at its destination and the reader discovers that the whole ship went "farmer" - planted the recreation decks, etc with crops and survived that way.

Based on what Andy and Casey calculated, this would have been impossible.

The pop-tents have air values, so they can get air from the Hab, but how much heat will come in through what I'm guessing is a relatively small diameter hose? And how will you get light for the plants in the tents?

That’s where the MAV fuel plant comes in.

You said the MAV got banged around a lot during the storm, so you might want to add that Mark checked it out and it was okay. Of course, you also said (in a note, not your story) that you're reworking the whole "Martian storm" scenario due to the thinness of the Martian atmosphere, so this is probably a moot point.

Everything was smooth until we hit the atmosphere. If you think turbulence is rough in a jetliner going 720kph, just imagine what it’s like at 28,000kph.

MAV: You may be confusing the MAV with the MDV. The MDV got banged around very badly. The MAV only tilted a little, risking falling over. It didn't get banged up by anything. And Watney has no way of knowing that it even tilted, so he wouldn't be concerned about the effects that might have had on the bottom half.

Martian re-entry: This is based on real mars probes which definitely use a heat shield for primary slowdown followed by parachutes for further deceleration. The atmosphere is extremely thin, but it's present, and re-entry speeds are so high it has an effect. The MAV's launch velocity is far, far slower and much less affected by the atmosphere. This is similar to launches from Earth. The ships we put in orbit aren't at risk of burning up from air friction at launch. Just at re-entry.